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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 5 |
| 5 | 15 |
| 6 | 90 |
| 7 | 7 |
| 8 | 35 |
| 9 | 525 |
| 10 | 47250 |
| 11 | 11 |
| 12 | 77 |
| 13 | 2695 |
| 14 | 1414875 |
| 15 | 66852843750 |
| 16 | 13 |
| 17 | 143 |
| 18 | 11011 |
| 19 | 29674645 |
| 20 | 41985913344375 |
| 21 | 2806877704512541816406250 |
| 22 | 17 |
| 23 | 221 |
| 24 | 31603 |
| 25 | 347980633 |
| 26 | 10326201751150285 |
| 27 | 433555011900329243987584396875 |
[2,3,6,5,15,90,7,35,525,47250,11,77,2695,1414875, 66852843750,13,143,11011,29674645,41985913344375, 2806877704512541816406250,17,221,31603,347980633, 10326201751150285,433555011900329243987584396875] |